Technical Field
The present invention relates to an on-board solar battery module.
Related Art
Conventionally, a type of solar battery module has been proposed where a backsheet, an encapsulant film in which solar battery cells are encapsulated, and a top film are stacked on top of each other, with the encapsulant film being sandwiched between the backsheet and the top film. This type of solar battery module is configured in such a way that, as described in Japanese Patent Application Laid-open (JP-A) No. 2012-33573, the reverse surface of the backsheet is supported by a frame-shaped support member and is secured via the support member to the roof of a vehicle.
Another type of solar battery module is being developed which, in contrast to the type of solar battery module that attaches to the roof of a vehicle as described above, itself serves as the roof of the vehicle and attaches to the vehicle body (vehicle skeleton members). This type of solar battery module is configured in such a way that the solar battery cells are secured via an encapsulant to the reverse side of an inorganic glass substrate serving as a top surface layer, with the backsheet being adhered to the back surface thereof.
The type of solar battery module that attaches to the roof of a vehicle as described above requires the support member for attachment to the roof of the vehicle, so the number of parts increases and the structure becomes complicated.
Meanwhile, the type of solar battery module used as the roof of a vehicle uses inorganic glass, which has a large mass, so attempts are being made to replace the inorganic glass substrate used for the top surface layer with a resin panel in order to reduce the weight of the solar battery module. In this case, the solar battery module is secured to vehicle skeleton members of the vehicle body, but it is preferred that the top surface layer be secured to the vehicle skeleton members. This is because when the back surface layer is secured to the vehicle skeleton members, there is the concern that, depending on the state of input of a load, a detachment load will act on the top surface layer of the solar battery module.
Furthermore, solar battery modules need to have a predetermined flexural rigidity so that they do not buckle. In a case where the solar battery module is secured to the vehicle skeleton members via the top surface layer (panel), it is necessary to join the reverse surface of the top surface layer to the vehicle skeleton members, so the only section of the solar battery module that becomes secured to the vehicle skeleton members is the top surface layer. In order to ensure that the solar battery module has the predetermined flexural rigidity at this section, the panel thickness of the top surface layer must be increased, so there is room for improvement with respect to weight reduction.